Funds are requested for an Agilent 6550 hybrid quadrupole-time-of-flight mass spectrometer (QTOF) with an Agilent 1290 ultra-high pressure liquid chromatography system (UHPLC). This equipment will be located in the Pasarow Mass Spectrometry Laboratory (PMSL), a collaborative core laboratory within the Semel Institute at UCLA. The PMSL does not currently have an instrument suitable for liquid chromatography/mass spectrometry (LC/MS) metabolomics or proteomics experiments. Such an instrument is essential to support the range of research projects in which the PMSL is involved and for which it has earned high regard. Acquisition of the requested equipment will ensure that the PMSL and its collaborating laboratories remain competitive in their respective fields and continue to make progress on the many important and exciting research projects on which they are working. The projects for which the requested instrument will be used encompass basic, translational, and clinical sciences, involving cutting-edge research in molecular biomarker screening for a number of diseases including Alzheimer's Disease and related disorders, a variety of cancers, and iron deficiency anemia, among others. The compounds that are being identified and quantified in these experiments are implicated in diverse biological phenomena including signal transduction, cellular communication, hormonal homeostasis, the addictive process, aging, immune responses, and inflammation. This application includes descriptions of projects from 23 collaborating laboratories: 6 are designated as Major and the remainder as Minor Projects, the basis of this distinction being overall time-commitment of instrument and personnel, all equally important and exciting. These collaborations are expected to occupy approximately 90% of instrument time. The remaining instrument time will be available to other collaborating groups for short-term exploratory research. The PMSL has the infrastructure to maintain and support the new equipment backed by an outstanding track record fostering the application of contemporary mass spectrometry to address important biological problems in science and medicine. Professor Faull, the PI on this application and the Director of the PMSL, Professor Whitelgge, de facto deputy director of the PMSL, and Research Assistants Joseph Capri and Farbod Fazlollahi, will be responsible for the day-to-day operation and maintenance of the new equipment. Professors Faull and Whitelegge have an exceptional reputation for the effective use of equipment purchased through the NIH SIG mechanism. This application represents a critical component of the effort by UCLA, the David Geffen School of Medicine, and The Semel Institute, to equip collaborative campus core laboratories with state-of-the- art instruments for cutting-edge research in metabolomics, proteomics, and related fields.